A rare Francis Bacon self-portrait is heading to the auction block for the very first time in May, having remained in private hands since it was painted 45 years ago.
Widely considered the artist's finest and most unique self-portrayals, Two Studies for a Self-Portrait will lead Sotheby's Evening Auction of Contemporary Art on May 11th, 2016 in New York.
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The double canvas, painted in 1970, has a presale estimate of $22 to $33 million dollars.
Oliver Barker, Sotheby's senior international specialist in contemporary art, calls it "number one" among all Bacon paintings.
"Discovering a work such as this is like finding gold dust," he said. "Worthy alongside the very finest self-portraits of Rembrandt, Van Gogh and Picasso."
Two Studies has only been exhibited twice before: Once at a 1971 retrospective of Bacon's work, and again in 1993 at Marlborough Fine Art, London.
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According to the Museum of Modern Art the the Irish-born, London-based figurative painter who died in 1992, was known for his "grotesque, emotionally-charged and raw imagery."
Ironically, Bacon disliked painting his own image. In 1979 admitted to a reporter how much he "loathed" his face and only painted it because "people were dying around me like flies and I've had nobody else to paint but myself."
In 2013, Bacon's triptych,Three Studies of Lucien Freud , set a world record at the time as the most expensive item of art ever sold at auction, selling for $142.4 million dollars at Christie's.
The New York Times identified the buyer as Elaine Wynn, ex-wife of casino mogul Steve Wynn.
Last year, five paintings by Bacon were stolen from a private residence in Madrid, Spain. The stolen works had an estimated combined worth of $30 million dollars.